Slave recording apparatus



Nov. 20, 1962 T. EDSTROM 3,065,468

SLAVE RECORDING APPARATUS Filed May 5, 1960 INVENTOR. THEODOR E EDSTROM ATTORNEY United States atent O 3,965,468 SLAVE RECORDTNG APPARATUS Theodore Edstrom, Parkview, Ohio, assignor to Union Carbide Corporation, a corporation of New York Filed May 5, 196%), Ser. No. 27,209 5 Claims. (31. 346-112) This invention refers to slave recording devices, that is those which reproduce a record as it is being recorded originally. It more particularly relates to such a device which is adapted to vary the maximum deflection of the record being recorded so as to enlarge or reduce the copy being made of the initial record. This invention further relates to such a device which is also adapted to make an original record directly without the necessity of a primary record.

It is the principal object of this invention to provide such a recorder which is simpler and more economical than those presently available.

This invention the comprises a recording device which is adapted to operate as a slave to a conventional rotating drum and pen type recorder or which in the alternative is adapted to operate as a direct recorder which is driven by the same means as conventional rotating drum and pen type recorder. The device operates by driving a reciprocating table through a rack and pinion gear train by either the X axis or the Y axis drive mechanism. The X axis or Y axis drive mechanism which does not drive the rack and pinion gears is linked to drive at least one scribe mounted independently of but adjacent to the reciprocating table in such manner as to be movable in the same plane as an perpendicular to the direction of movement-pf the table.

Understanding of this invention will be facilitated by reference to the accompanying drawing which is an isometric view of the recording device according to this invention with parts thereof broken away. The device is shown positioned in operating relation to a conventional rotating drum and pen recorder of which only a fragmentary portion is illustrated.

Referring now to this figure, a drive shaft generally adapted to drive a conventional rotating drum 12 has a pinion gear 14 axially mounted thereon. This pinion gear 14 is meshed with a rack gear 16 which is mounted on a reciprocating table 18. Movement of the drive shaft 10 causes the pinion gear 14 to move the table through the rack gear 16.

The drive mechanism for the pen of the rotating drum and pen recorder (not shown) drives a pulley 20 through a belt 22. The pulley 20 is axially attached to an extension shaft 24 which has a bevel gear 26 mounted thereon. This bevel gear 26 meshes with another bevel gear 28 axially mounted on a second shaft 30. Mounted on the shaft 30 is a pulley 32 which drives a deflection changing linkage which preferably comprises an endless belt 34 and a pulley 36 freely mounted on an axle 37.

Optionally, a second pulley 32 of different diameter may be mounted on the shaft 30 as well as a corresponding pulley 36 on the axle 37, along with another endless belt 34'. This readily permits ditferent size slave recordings to be made. Securely attached to the axle 37 inside the pulleys 36 and 36' are two capstans 39 and 39' of the same diameter which turn with the axle 37. One end of a scribe drive cable 48 is secured to the capstan 39 by a number of turns in the clockwise direction. From there, the drive cable 48 is directed upward and around a pulley 41, along a cross arm 43, around a pulley 44, back along cross arm 43, over a pulley 46 and finally the other end of cable 48 is secured around the capstan 39' by an equal number of turns in the counter clockwise direction. At least one scribe 38 is adjustably attached to the cable 48 by a thumbscrew 47 and when the cable 48 moves the scribe 38 is driven in a direction in the same plane as, but perpendicular to, the movement of the table 18, and a slave recording will be traced on a sheet of paper 40 provided on the table 18. The tension in the drive cable 48 may be adjusted by means of a thumbscrew 50 which controls theposition of the axle 37 which carries the cable capstans 39 and 39'.

A recording is made by engaging the rack 16 and the pinion 14 and engaging the scribe drive cable 48 by engaging the selected drive pulley 36 or 36' with the axle 37 by means of a friction clutch engagement which consists of tightening the corresponding thumbscrew 45 or 45 until the pulley 36 or 36' turns with the axle 37 by friction engagement with the capstan 39 or 39.

One of the outstanding advantages of this invention is the fact that the rack gear 16 is movably mounted on members 42 and held thereon by set screws so as to be adjustable in distance from the drum driving shaft 10. This permits a variety of different sized pinion gears 14 thereby allowing various speed ratios to exist between the table movement and the drum driving shaft movement. This makes the device extremely flexible in that reduced, enlarged or identical copies of data may be made. As outlined above, the drive pulleys may also be varied in size to change the relative size of the copy produced.

It is highly desirable that each of the drive mechanisms be provided with means for disengaging them in order to enable the user to set both axes at zero. In the illustrated recorder, the pen drive mechanism may be disengaging by disengaging the friction clutches 45 and 45. The drum mechanism may be disengaged by lossening a knob 51 and disengaging pinion 14 from rack 16.

Thus, the relative scale of either the X axis or Y axis may be expanded or reduced independently of each other or both scales may be reduced or expanded proportionately to have an overall larger or smaller record of the data measured. Multiple copies may be made simply by securing a multiplicity of scribes on the drive cable and suitably adjusting the gears and pulleys to the proper scales.

What is claimed is:

l. A mechanical slave recorder for a recording instrument having a rotatable drum and a pen, which recorder comprises a movable table; a rack on said table; a pinion gear in driven engagement with a shaft on the rotatable drum of said recording instrument; said pinion gear being in driving engagement with said rack whereby to impart reciprocal movement to said table in response to rotation of said drum; a scribe in Writing relationship to said table, said scribe being connected to a driving mechanism for the pen of said recording instrument by a linkage comprising a pulley in driven engagement with said pen driving mechanism and a pair of shafts mounted at to each other and coupled by bevel gears mounted thereon; one of said pair of shafts of said linkage being in driven relation with said pulley and the other of said pair of shafts having a pulley axially mounted thereon; a movable support for said scribe and an endless belt connecting said support to said last-mentioned pulley, whereby to impart relative movement between said scribe and said table in response to movement of said pen driving mhechanism.

2. The slave recorder of claim 1 wherein said rack is adjustably mounted on said table and the diameter of said pinion gear may be varied in accordance with the position of said rack.

3. A slave recorder as described in claim 1 wherein said other end of said pair of shafts is provided with two pulleys of different diameters axially mounted thereon.

4. A slave recorder as described in claim 1 wherein said scribe linkage is disengageable from said pen driving mechanism of said recorder and said pinion gear is disengageable from said rack. v r

5. A slave recorder as described in claim 1 wherein 5 said movable support for said scribe is a movable drive cable, the ends of which are secured to two capstans mounted on a shaft in driven engagement with said axially mounted pulley by said endless belt.

References ited in the file of this patent UNITED STATES PATENTS France Feb. 3, 1954 

